Artem Russakovskii's questions

I have recently run into an issue after switching to Cloudflare, and the solution is to basically stop Cloudflare from caching 404 responses.

In our load-balanced multi-server setup, occasional 404s happen, but they're quickly fixed by rsync (via lsyncd). Before Cloudflare, a re-request to the 404ed file would very quickly become 200 as rsync does its job.

However, since Cloudflare caches all data based on the caching header, and neither apache nor nginx send a no-cache header for 404s, Cloudflare ends up caching the 404 response for a while.

I've been searching for a solution to globally add such a header for 404s in both apache and nginx (globally, for all hosted domains), but so far have come up blank.

Can anyone help?

Thank you.

I've been at this for hours and I can't figure out a clean solution.

Basically, I have an nginx proxy setup, which works really well, but I'd like to handle a few urls more manually. Specifically, there are 2-3 locations for which I'd like to set proxy_ignore_headers to Set-Cookie to force nginx to cache them (nginx doesn't cache responses with Set-Cookie as per http://wiki.nginx.org/HttpProxyModule#proxy_ignore_headers).

So for these locations, all I'd like to do is set proxy_ignore_headers Set-Cookie;

I've tried everything I could think of outside of setting up and duplicating every config value, but nothing works.

I tried:

• Nesting location directives, hoping the inner location which matches on my files would just set this value and inherit the rest, but that wasn't the case - it seemed to ignore anything set in the outer location, most notably proxy_pass and I end up with a 404).
• Specifying the proxy_cache_valid directive in an if block that matches on $request_uri, but nginx complains that it's not allowed ("proxy_cache_valid" directive is not allowed here).
• Specifying a variable equal to "Set-Cookie" in an if block, and then trying to set proxy_cache_valid to that variable later, but nginx isn't allowing variables for this case and throws up.

It should be so simple - modifying/appending a single directive for some requests, and yet I haven't been able to make nginx do that.

What am I missing here?

Is there at least a way to wrap common directives in a reusable block and have multiple location blocks refer to it, after adding their own unique bits?

Thank you.

Just for reference, the main location / block is included below, together with my failed proxy_ignore_headers directive for a specific URI.

location / {
  # Setup var defaults
  set $no_cache "";

  # If non GET/HEAD, don't cache & mark user as uncacheable for 1 second via cookie
  if ($request_method !~ ^(GET|HEAD)$) {
    set $no_cache "1";
  }

  if ($http_user_agent ~* '(iphone|ipod|ipad|aspen|incognito|webmate|android|dream|cupcake|froyo|blackberry|webos|s8000|bada)') {
    set $mobile_request '1';
    set $no_cache "1";
  }

  # feed crawlers, don't want these to get stuck with a cached version, especially if it caches a 302 back to themselves (infinite loop)
  if ($http_user_agent ~* '(FeedBurner|FeedValidator|MediafedMetrics)') {
    set $no_cache "1";
  }

  # Drop no cache cookie if need be
  # (for some reason, add_header fails if included in prior if-block)
  if ($no_cache = "1") {
    add_header Set-Cookie "_mcnc=1; Max-Age=17; Path=/";
    add_header X-Microcachable "0";
  }

  # Bypass cache if no-cache cookie is set, these are absolutely critical for Wordpress installations that don't use JS comments
  if ($http_cookie ~* "(_mcnc|comment_author_|wordpress_(?!test_cookie)|wp-postpass_)") {
    set $no_cache "1";
  }

  if ($request_uri ~* wpsf-(img|js)\.php) {
    proxy_ignore_headers Set-Cookie;
  }

  # Bypass cache if flag is set
  proxy_no_cache $no_cache;
  proxy_cache_bypass $no_cache;

  # under no circumstances should there ever be a retry of a POST request, or any other request for that matter
  proxy_next_upstream off;
  proxy_read_timeout 86400s;

  # Point nginx to the real app/web server
  proxy_pass http://localhost;

  # Set cache zone
  proxy_cache microcache;

  # Set cache key to include identifying components
  proxy_cache_key $scheme$host$request_method$request_uri$mobile_request;

  # Only cache valid HTTP 200 responses for this long
  proxy_cache_valid 200 15s;

  #proxy_cache_min_uses 3;

  # Serve from cache if currently refreshing
  proxy_cache_use_stale updating timeout;

  # Send appropriate headers through
  proxy_set_header Host $host;
  # no need for this proxy_set_header X-Real-IP $remote_addr;
  # no need for this proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

  # Set files larger than 1M to stream rather than cache
  proxy_max_temp_file_size 1M;

  access_log /var/log/nginx/androidpolice-microcache.log custom;
}

This one has been bugging me for a while: I want to use the marvelous GNU watch command to run a few custom aliases and functions that are defined in my .bashrc, but it is never able to run anything except bash built-ins or binaries.

watch -d foo

The output is always: foo: command not found

How can I make it inherit my environment or use the .bashrc?

Thank you.

I have a few network drive mappings that I want to be available to various programs upon reboot. However, they remain disconnected until I visit them manually.

If a program, such as OneNote which reads notes shared on a network drive, tries to connect, it does not see the share and does not cause auto-reconnect.

I am looking for a fully automated solution, preferably just a setting to make Windows natively reconnect on machine boot.

For example, right now drive Y and Z are disconnected and X is connected because I accessed it manually:

Edit: I have to change my question slightly but with quite a significant impact on the answers. The drives are indeed NOT available at logon. They only become reachable after I open an ssh tunnel.

Therefore, the main question is - how do you make applications force the drive alive when they try to access it?

I guess another approach would be to automatically run a script when the tunnel gets established. It's probably my best bet if the above is not possible.